• Title/Summary/Keyword: SSB

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Radiation-induced DNA strand breaks in EL4 cells and mouse spleen lymphocytes (방사선에 의한 EL4 마우스 백혈병세포 및 정상 마우스 비장 임파구 DNA strand breaks의 측정)

  • Kim, Sung-ho;Kim, Tae-hwan;Chung, In-yong;Yoo, Seong-yul;Cho, Chul-koo;Chin, Soo-yil
    • Korean Journal of Veterinary Research
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    • v.31 no.3
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    • pp.329-335
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    • 1991
  • The filter elution technique was used to assay $^{60}Co$ $\gamma$ ray-induced DNA strand breaks(SB) in EL4 mouse leukemia cell and mouse spleen lymphocyte. The lymphocytes were stimulated with lipopolysaccharide (LPS, $20{\mu}g/ml$) to label $[^3H]$ thymidine. EL4 cells and lymphocytes in suspension were exposed at $0^{\circ}C$ to 0Gy, 1Gy, 5Gy, 10Gy or l5Gy for DNA single strand breaks(SSB) assay and 0Gy, 25Gy, 50Gy, 75Gy or 100Gy for DNA double strand breaks(DSB) assay of $^{60}Co$ radiation and elution procedure was performed at pH12.1 and 9.6. The number of DNA strand breaks increased with increasing doses of r rays. The strand scission factor(SSF) was estimated in each experiment (eluted volume 21ml). The slope of SSB EL4 cells was $0.01301{\pm}0.00096Gy^{-1}$ (n=5), the slope of SSB for lymphocytes was $0.01097{\pm}0.00091Gy^{-1}$ (n=5) and the slope of DSB for lymphocytes was $0.001707{\pm}0.0000573Gy^{-1}$ (n=5). Thus EL4 cells were more sensitive to induction of DNA SSB by ionizing radiation than lymphocytes (p<0.005). The ratio of slope of dose-response relationship (SSF versus dose) of lymphocytes DNA SSB as compared with the slope of DNA DSB was 6.4.

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A Study on the Application of TRS Communication System for the Small Fishing ship (소형어선과의 통신을 위한 TRS통신방식의 도입에 관한 연구)

  • 김정년;최조천;조학현
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2002.11a
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    • pp.196-201
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    • 2002
  • The SSB(Single Side Band) communication in the 27MHz band has mainly been using between fishiery station and small fishing ship less than 10tons, but the most of small fishing ship are depend on cellular system. When accident for small ship at sea happens, It's very important to communicate continuously for preventing the collision and taking action. At present it is hard to control small fishing ship and provide information properly by using 27MHz SSB channel. Therefore in this paper We present TRS communication system applied for small fishing ship to protect the safy and life at sea and to prepare for emmergency, and also validate it's application.

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Design and Fabrication of 5.5GHZ SSB optical modulator with polarization reversed structure (LiINbO3 기판의 분극반전을 이용한 5.5 GHz 대역 SSB 광변조기의 설계 및 제작)

  • Jeong, W.J.;Kim, W.K.;Yang, W.S.;Lee, H.M.;Lee, H.Y.;Kwon, S.W.
    • Korean Journal of Optics and Photonics
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    • v.17 no.2
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    • pp.175-180
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    • 2006
  • A single sideband(SSB) modulator operating at 5.5 GHz was fabricated by polarization inversion techniques. The dimension of domain inversion in a $LiINbO_3$ Mach-Zehnder structure was precisely controlled so that the RF signal applied on two Mach-Zehnder arms gives rise to $90^{\circ}$ effective phase difference. The single sideband suppression was maximized by optimization of the polarization status of the optical input and by the DC bias value. The fabricated device showed the center frequency of 5.8 GHz and the maximum sideband suppression of 33dB, where the bandwidth of 15 dB sideband suppression ranged over a 2.5 GHz span. The optical phase delay could be regulated by the DC bias voltage, fur example, the enhanced optical modulation sideband was distinctively switched from the upper sideband to the lower sideband by changing the DC bias voltage from 1.9 V to -10.6 V.

Improved Transmitter Power Efficiency using Cartesian Feedback Loop Chip

  • Chong, Young-Jun;Lee, Il-Kyoo;Oh, Seung-Hyeub
    • Journal of electromagnetic engineering and science
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    • v.2 no.2
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    • pp.93-99
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    • 2002
  • The Cartesian loop chip which is one of key devices in narrow-band Walky-Talky transmitter using RZ-SSB modulation method was designed and implemented with 0.35 Um CMOS technology. The reduced size and low cost of transmitter were available by the use of direct-conversion and Cartesian loop chip, which improved the power efficiency and linearity of transmitting path. In addition, low power operation was possible through CMOS technology. The performance test results of transmitter showed -23 dBc improvement of IMD level and -30 dEc below suppression of SSB characteristic in the operation of Cartesian loop chip (closed-loop). At that time, the transmitting power was about 37 dBm (5 W). The main parameters to improve the transmitting characteristic and to compensate the distortion in feed back loop such as DC-offset, loop gain and phase value are interfaced with notebook PC to be controlled with S/W.

A Study on the Remote Control for a Integrated Communication Systems (통합통신시스템의 원격제어에 관한 연구)

  • 조학현
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.7 no.1
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    • pp.19-25
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    • 2003
  • The radio communications by SSB and VHF transceivers are still used very efficiently in coast stations. The SSB and VHF equipments are very important to transmit and receive informations in the sea and the land. The communication system by the conventional SSB and VHF transceivers between a coast station and a terminal is an one-to-one system. In this dissertation, however, the conventional one-to-one system is expanded to one-to-multiple systems. Then, frequencies can be used effectively for distress, urgency, safety traffic. In addition, one to multi-number systems can be used to interrupt. When the ICS equipments are set up to the VHF transceiver. It is possible to communicate with ship in far distance the communication range can be enlarged. The line switching system by the ICS is to be remote-controlled by ASK modulated PTT signals and audio signals. An ICS can change a connection between terminal and transceiver through a circuit switching system at any time. For this purpose, the author has researched and developed a ASK transmission system, ICS system, control algorithm, multiprocessor system, and monitoring system. As a conclusion, the developed line switching control systems and equipments can be used effectively for maritime communication, military communication, fishery communication, etc.

Design and Implementation of Cartesian Loop Chip for the Narrow-Band Walky-Talky (협대역 무전기용 카테지안 루프 칩 설계 및 구현)

  • 정영준;최재익;오승엽
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.9C
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    • pp.871-878
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    • 2002
  • The cartesian loop chip which is one of key devices in narrow-band Walky-Talky transmitter using RZ-SSB modulation method was designed and implemented with 0.35 ㎛ CMOS technology. The reduced size and low cost of transmitter were available by the use of direct-conversion and cartesian loop chip, which improved the power efficiency and linearity of transmitter. In addition, low power operation was possible through CMOS technology. The performance test results of transmitter showed -23㏈c improvement of IMD and -30㏈c below suppression of SSB characteristic in the operation of cartesian loop chip (closed-loop). At that time, the transmitting power was about 37㏈m (5W). The main parameters to improve the transmitting characteristic and to compensate the distortion in feed back loop such as DC-offset, loop gain and phase value are interfaced with notebook PC to be controlled with S/W.

The Characteristics of Bacteria Isolated from Ordinary Korean Soy Sauce and Soybean Paste (한국(韓國) 재래식(在來式) 간장 및 된장에서 분리(分離)한 세균(細菌)의 특성(特性))

  • Kwon, Oh-Jin;Kim, Jong-Kyu;Chung, Yung-Gun
    • Applied Biological Chemistry
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    • v.29 no.4
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    • pp.422-428
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    • 1986
  • The bacteria were isolated from ordinary Korean soy sauce and soybean Paste. After isolation, we investigated the bacteria which produces the characteristic flavor of ordinary Korean soy sauce and soybean paste, nothing the aroma, presence of amino acids, and free sugars. The results were obtained as follows. The bacteria isolated from ordinary Korean soy sauce and soybean paste were various Bacillus species. The isolated bacteria produced characteristic orders: 'Meju' order, the characteristic saline odor of ordinary Korean soy sauce or ordinary Korean soybean paste order, and enzymes: protease and amylase. The good characteristic saline odor of ordinary Korean soy sauce was produced by Bacillus licheniformis$(SSB_3)$. The good odor of ordinary Korean soybean paste was produced by Bacillus polymyxa$(SSB_4)$, Bacillus species$(SPB_1)$, Bacillus brevis$(SPC_2)$, and Bacillus lichniformis$(SPC_{2-1})$.

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